Predicted First Clocks
Past Known Clocks Modern Day Clocks
A clepsydra is the first predicted method of clock. It's dated 1600BC..It's originally known to be from Ancient Egypt known as a water clock. The clepsydra worked like an hourglass except with water. They had giant jugs of water with a tiny hole in the bottom attached to another jug with markings that indicated different times of the day. As the water dropped the pressure meter dropped pointing to a new time. From the very beginning it was used by Greek for the law court and intervals before the third century B.C. Soon Rome, Arab, and China started using clepsydras as clocks.
Clepsydras were the first clocks but weren't the only clocks for long. Soon came sundials. Sundials are much more popular or known by more people now then clepsydras are. Sundials are a different function then clepsydras. Sundials use the position of the sun which means they can only be used outside causing a disadvantage. Sundials use the theory of shadow. The sundial is a round platform with roman numerals around the edges. When the sun is directly above the earth it will point to twelve or one o'clock depending exactly where it is.
